Flying picket

Picketing is a form of protest in which people (called picketers) congregate outside a place of work or location where an event is taking place. Often, this is done in an attempt to dissuade others from going in ("crossing the picket line"), but it can also be done to draw public attention to a cause. Picketers normally endeavor to be non-violent. It can have a number of aims, but is generally to put pressure on the party targeted to meet particular demands and/or cease operations. This pressure is achieved by harming the business through loss of customers and negative publicity, or by discouraging or preventing workers and/or customers from entering the site and thereby preventing the business from operating normally.

Picketing is a common tactic used by trade unions during strikes, who will try to prevent dissident members of the union, members of other unions and non-unionised workers from working. Those who cross the picket line and work despite the strike are known pejoratively as scabs.

Informational picketing is the legal name given to the type of picketing described above. Informational picketing, as described by Merriam-Webster's Dictionary of Law, entails picketing by a group, typically a labour or trade union, which inform the public about a matter of concern important to the union. It is a popular picketing technique for nurses to use outside of healthcare facilities. For example, on April 5, 2006 nurses of the UMass Memorial Medical Center (UMMHC) participated in two separate informational picketing events to protect the quality of their nursing program. Informational picketing was used to gain public support and promote further bargaining with management.

A mass picket is an attempt to bring as many people as possible to a picket line to demonstrate support for the cause. It is primarily used when only one workplace is being picketed or for a symbolically or practically important workplace. Due to the numbers involved, a mass picket may turn into a potentially unlawful blockade.

Secondary picketing people picketing locations that directly connected to the issue of protest. That would include component suppliers on which the picketed business relies, retail stores that sell products by the company against which is being picketed, sister companies of the company involved in the dispute and the private homes of the company's management. In many jurisdictions, secondary pickets do not have the same civil law protection as primary pickets.

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